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  <title>Document</title>
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  <script>

    //  true
    //  false:  0 NaN '' null undefiend -0 +0

    console.log( Boolean('0') )  // true
    console.log( Boolean(-0) )  // false


    console.log( Boolean('qwe') )  // true
    console.log( Boolean(123) )  // true
    console.log( Boolean(0) )  // false
    
    console.log( Boolean(-1) )  // true
    console.log( Boolean(undefined) )  // false
    console.log( Boolean(null) )  //false
    console.log( Boolean({}) )  // true
    console.log( Boolean([]) )  // true
  </script>
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